Formflo Limited

Ronald C Andriessen

Gordon Sidney Connell

Peter J Holt

An annular workpiece 6 is rolled between two oppositely disposed forming rolls 2, 4, and two oppositely disposed growth rolls 22 and 24 acting at right angles to the line of action of the forming rolls. The forming rolls 2, 4, are brought together to roll form the workpiece 6 to a wall thickness dependent upon its weight, and the advance of the growth control rolls 22, 24 is controlled to a position which is also dependent upon the weight of the workpiece 6.

Rolling annular workpieces

Rings are made from tube stock (10) or bar stock by cold rolling successive end portions (78) of the latter between profile rolling elements (42, 44) of a plurality of rollers which also include parting tool elements (40) for making a parting groove, also by cold rolling. The parting groove is formed, by the parting tool elements while the profile rolling operation takes place during the latter part of the parting groove forming operation. With bar stock, a bore is made through the end portion of the stock, e.g. after the parting groove is formed, the latter having a depth just insufficient for final parting-off, which takes place during subsequent machining of the bore of the ring. A locating groove (76, 80) is also formed, by means of a grooving tool (74), simultaneously with the rolling operation.

Making rings from tube or bar stock

The invention relates to methods and apparatus for making rings from tube stock (10) by a part-off rolling tool (12,15) which is advanced radially into the tube stock to form successive rings, e.g. annular blanks for subsequent roll forming into bearing rings. The tube stock is indexed forward after separation of each ring. Errors in the length of tube stock indexed forward each time are contained by forming a locating groove (47) on the tube stock by means of a groove-rolling tool (40) set at an appropriate axial distance from the part-off rolling tool (12) and moved radially with it. In the next cycle the groove (47) automatically centers the part-off tool as the latter begins its advance into the tube stock, so as to give the correct axial length of the finished ring. The part-off tool is stopped before fully penetrating the tube wall, which is then machined. Final separation takes place during this machining or in a subsequent finishing pass by the part-off tool.

Making rings from tube stock

A method of rolling an initially annular workpiece between forming rolls in which after the forming rolls have been fully advanced they are retracted initially slowly for a predetermined distance. The forming rolls can then be further retracted at a greater speed. The slow retraction reduces the out of roundness of the finished rolled ring.

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Cheltenham, United Kingdom

Ronald C Andriessen